Heretofore, microstructures, such for example as leukocytes, were prepared for microscopic examination by the wedge and cover-slide method or by a centrifuge whereby a blood smeared slide was prepared. On such microscopic slides, the leukocytes were randomly distributed and the observer had to search them out for examination and counting. Due to the random arrangement of the leukocytes on a blood smeared slide much time would be required by the operator to find each of the leukocytes before they could be examined and counted.